CVE-2026-48798

SSH.NET: ScpClient Recursive Download Allows Arbitrary File Write via Server-Controlled SCP Filenames

Published Aug 18, 2026 CVSS 3.1 · 7.1 High EPSS < 1% KEV · Not listed
Description
SSH.NET is a Secure Shell (SSH) library for .NET. In 2025.1.0 and earlier, ScpClient.Download(string directoryName, DirectoryInfo directoryInfo) trusts file and directory names returned by a remote SCP server and combines them with the requested local directory without containment validation, allowing a malicious, compromised, or man-in-the-middle server to use ../ sequences or absolute paths to create or overwrite files anywhere writable by the client process. This issue is fixed in version 2026.0.0.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Github GHSA Github GHSA GHSA-q939-rpr3-3284 SSH.NET: ScpClient Recursive Download Allows Arbitrary File Write via Server-Controlled SCP Filenames
History
Type Values Removed Values Added
First Time appeared Sshnet
Sshnet ssh.net
Vendors & Products Sshnet
Sshnet ssh.net
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
Description SSH.NET is a Secure Shell (SSH) library for .NET. In 2025.1.0 and earlier, ScpClient.Download(string directoryName, DirectoryInfo directoryInfo) trusts file and directory names returned by a remote SCP server and combines them with the requested local directory without containment validation, allowing a malicious, compromised, or man-in-the-middle server to use ../ sequences or absolute paths to create or overwrite files anywhere writable by the client process. This issue is fixed in version 2026.0.0.
Title SSH.NET: ScpClient Recursive Download Allows Arbitrary File Write via Server-Controlled SCP Filenames
Weaknesses CWE-22
CWE-73
References
Metrics cvssV3_1

{'score': 7.1, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:L'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
Aug 18, 2026, 3:28 PM
Reserved
May 22, 2026, 8:18 PM
Status
Awaiting Analysis
Published
Aug 18, 2026, 3:16 PM
Modified
Oct 22, 2026, 10:10 PM